The present disclosure relates generally to electronic displays and, more particularly, to techniques for correcting for voltage offsets associated with gamma bus amplifiers used in such displays. This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Liquid crystal displays (LCDs) are commonly used as screens or displays for a wide variety of electronic devices, including such consumer electronics as televisions, computers, and handheld devices (e.g., cellular telephones, audio and video players, gaming systems, and so forth). Such LCD devices typically provide a flat display in a relatively thin and low weight package that is suitable for use in a variety of electronic goods. In addition, such LCD devices typically use less power than comparable display technologies, making them suitable for use in battery powered devices or in other contexts where it is desirable to minimize power usage.
LCD devices typically include thousands (or millions) of picture elements, i.e., pixels, arranged in rows and columns. For any given pixel of an LCD device, the amount of light that viewable on the LCD depends on the voltage applied to the pixel. Typically, LCDs include driving circuitry (e.g., gamma block) for converting digital image data into analog voltage values that may be supplied to pixels within a display panel of the LCD. Traditionally, the driving circuitry for N-bit displays includes 2N wires that have 2N different analog voltage levels that represent 2N gray levels. All of the 2N wires are typically coupled to a unit source driver for each pixel in the display. Accordingly, for an 8-bit display, 256 wires are used, and such a large number of wires occupies valuable space on the display.
To save space, the number of wires coupled between the driving circuitry and the unit source driver may be reduced using multiplexers. For instance, 256 wires traditionally used in an 8-bit display may be routed to sixteen different 16-wire multiplexers. The sixteen multiplexers may then multiplex the received voltage values over time and provide 16 different multiplexed outputs that may be used to represent the 256 voltage using only 16 wires. Each of these multiplexer outputs is typically coupled to a gamma bus amplifier that buffers each multiplexed signal to allow the multiplexed signal time to settle. The gamma bus amplifiers may then output buffered multiplexed signals to the unit source driver of a pixel. The unit source driver may then determine the analog voltage level that corresponds to the buffered multiplexed signal and may forward this analog voltage level to the pixel.
Unfortunately, each gamma bus amplifier has a voltage offset value, which can cause visual performance issues when the unit source driver transitions between two voltage values that are output by two different gamma bus amplifiers. Thus, although this multiplexing technique may save space, it may not produce the same visual performance characteristics as the traditional driving circuitry.